[RFC PATCH 17/19] cpufreq: stop checking for cpufreq_driver being present in cpufreq_cpu_get

From: Juri Lelli
Date: Mon Jan 11 2016 - 12:38:46 EST


After cpufreq_driver_lock() is acquired in cpufreq_cpu_get() we are sure
we can't race with cpufreq_policy_free() (which is in the path that ends
up removing cpufreq_driver). We can thus safely remove check for
cpufreq_driver being present (which is a leftover from commit
6eed9404ab3c ("cpufreq: Use rwsem for protecting critical sections")).

Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Juri Lelli <juri.lelli@xxxxxxx>
---
drivers/cpufreq/cpufreq.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 797bfae..6c9bef7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -282,15 +282,15 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
if (WARN_ON(cpu >= nr_cpu_ids))
return NULL;

- /* get the cpufreq driver */
read_lock_irqsave(&cpufreq_driver_lock, flags);

- if (cpufreq_driver) {
- /* get the CPU */
- policy = cpufreq_cpu_get_raw(cpu);
- if (policy)
- kobject_get(&policy->kobj);
- }
+ /*
+ * If we get a policy, cpufreq_policy_free() didn't
+ * yet run.
+ */
+ policy = cpufreq_cpu_get_raw(cpu);
+ if (policy)
+ kobject_get(&policy->kobj);

read_unlock_irqrestore(&cpufreq_driver_lock, flags);

--
2.2.2